Code review comment for lp:~pcsol/openobject-server/print_trunk

I'm a bit puzzled by this merge prop, and the 'It work for me' comment... (I would have been happy to discuss the proposal but xrg's comment remains alone. Also, this code adds more than the two mentioned field: an seemingly unused attachment_use; more importantly the variable number will be uninitialized (numner, instead of number, is initialized).